Circuit closer



Patented F cl). 4, 1947 CIRCUIT CLOSER Harold P. Detwiler, Fort Monroe, Va., assignor to the United States of America, as represented by the Secretary of War Application March 9, 1935, Serial No. 10,141

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) 4 Claims.

This. invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a circuit closer of the type described and claimed in Patent No. 1,662,979, issued March 28, 1928, and entitled Circuit closer; more particularly it is directed to a circuit closing assembly adapted to be used in connection with the system of submarine mine control, forming the subject matter of Patent No. 1,901,185, issued March 14, 1933, and entitled Submarine mine control.

One object of this invention is to provide a circuit closing assembly to be used in connection with impact fired submarine mines, which will insure completion of the detonating circuit whenever the mine has been sufliciently tilted by impact to dispose the components of the circuit closer in operative or firing relations.

Another object of this invention is to provide a circuit closer for submarine mines having facilities for retaining the spherical contact between the electrodes and in circuit closing position until it has been released by the remotely controlled electro-responsive device.

Another object of this invention is to provide a circuit closer which is self-restoring and nonjamming; which will insure a wiping contact between the steel spherical contact and the movable contact plate; and to effect; a circuit closer which is simple, economical, rugged in construction and efficient in operation.

With these and other objects in view, this invention consists in certain novel details of construction, combination and arrangement of parts to be more particularly hereinafter set forth in claims.

Briefly stated, this invention consists of a circuit closer adapted to be suitably housed Within a submarine mine and comp-rising, insulated electrodes normally disposed in perpendicular position, one of the electrodes being formed with a seat having upwardly and outwardly flared walls, a, contact plate situated above and in vertically spaced relation to the seat, said plate being movable rectilinearly along and angularly about its vertical axis, a tapered plunger projecting through the central portion of the plate, a spherical member of conducting material disposed upon said seat, said member when the electrodes are tilted from the perpendicular descending the inclined wall of its seat into engagement with the contact plate and plunger to establish an electrical path between the electrodes, the plunger preventing return of the spherical member to its normal position and an electroresponsive device coacting with the plunger to remove the latter from the path of the spherical member to restore said member to its original or open-circuit position,

Referring more particularly to the accompanying drawing in which corresponding part are indicated by similar reference characters,

Fig. 1 is a transverse vertical section partly in elevation, illustrating the arrangement of the components by improved assembly under opencircuit conditions.

Fig. 2 is a similar view, illustrating the arrangement of the circuit-closing components under closed-circuit conditions.

For the sake of convenience this invention will be discussed in the order of its principal components, i. e., assembly casing A and A, upper and lower electrodes B and C, and spherical contact D for establishing an electrical path between the electrodes and electro-responsive device E.

Assembly casings A and A The various components of this invention are housed within a cylindrical casing A of suitable insulating material. Externally, casing A is formed at its upper end with a reduced threaded portion l to receive a suitably threaded metallic cap 2, and enclosing at its lower end a similar casing A of insulating material with annular reduced portions 3 and 4, as clearly shown in Figs. 1 and 2 of the drawing.

The interior of casing A is cored to form upper and lower chambers 5 and 1, respectively, adapted to receive the electro-responsive device E, upper and lower electrodes B and C, and spherical contact D, which under closed circuit conditions bridges the electrodes.

Upper and lower electrodes Lower electrode C consists of a metallic annulus 9 molded within the casing A. Annulus 9 is reduced to form extension In, adapted to project into and terminate flush with the lower edge of bore 8.

Electrode C is centrally formed with a circular recess I l, which spreads at its upper end into the frusto-conical section of a cone to produce the inclined surface I 2, constituting a race for spherical contact D. The lower end of recess ll opens into bore I3 of extension l0, and the latter is internally threaded to receive a terminal plug (not shown). A ring M of insulating material seats within the recess II, the surface of the ring being 3 suitably inclined to form a continuation of sur face I2. This ring functions as a seat for spherical contact D when the latter is in inoperative or open-circuit position,

Upper electrode B is composed of circular contact plate is and solenoid plunger I 6. The diameter of plate i5 is less than that of chamber 6, in which it is disposed, so that suificient clearance will be provided to enable the plate to be tilted when engaged by the spherical contact D, as shown in Fig. 2 of the drawing. The lower surface of contact I5 is normally held throughout its circumference against its seat I! by spiral spring I8, interposed between the bottom of the solenoid housing, hereinafter to be mentioned, and the upper surface of plate l5. To prevent spring l8 from being displaced laterally, the end of the lowermost spiral has been soldered to the upper face of plate i5. Central of plate l5 there is found an opening 25 for the passage of the lower tapered end of plunger l6. Normally the lower end of plunger it rests upon spherical contact D and its weight is such that the spherical contact will be held in open circuit position (Fig. 1), until the mine housing the circuit closer has been tilted to approximately 45 from the vertical.

Electra-responsive device Seated within chamber 5 of the casing A is an annular meta llic housing 19 which is adapted to contain in its upper portion the electro-responsive device E and forms chamber 6 in its lower portion. Llectro-responsive device E comprises a solenoid housing formed by upper and lower metallic plates 20 and 28, respectively, and a vertically disposed sleeve 23 around which is turned solenoid winding 22. The lower end of sleeve 23 is formed into the reduced extension 23. Upper and lower plates of insulating material 2 l and M, respectively, are disposed around sleeve 23 and within upper and lower metallic plates 20 and 29 of the electro-responsive device E.

One end of solenoid winding 22 is connected to a contact-spot 25 in the plate 20". The other end of winding-22 is fastened to metallic screw M by means of nuts 25 and 26. Screw 2 is insulated from plate 26 by means of bushing 24 and plate 2'5, both of which are of suitable insulating material. Screw 24 is in electrical contact with metallic plate 27 which is in turn in electrical contact with metallic cap 2 of the easing A, and thus the winding 22 is electrically in connection with cap 2. Screw 29, similar to screw 26, with a nut 3i) and bushing 3|, similar to nut 25 and bushing 24, are so disposed as to provide an additional means of fastening the electroresponsive device E firml to plate 2?.

In addition to functioning as a core for winding 22, sleeve 23 also serves as a housing for the head 18 of solenoid plunger I6, slidably mounted within the sleeve. The movement of head N5 of the solenoid plunger is limited to the area defined by plate 2'! and the shoulder 28 of the reduced extension 23 of the sleeve 23, as clearly shown in Figs. 1 and 2 of the drawing. Sleeve 23 is also utilized as a shield to prevent passage of the lines of force from windings 22 to spherical contact B, as will be understood without further discussion.

There are suliicient turns in winding 22 to insure positive lifting of solenoid plunger 56, when a suitable current is impressed upon said windings. This invention is adapted to be used in connection with the submarine mine control system disclosed in the patent to Paul R. Nelson, is-

sued March 14, 1933, No. 1,901,185. According to this system, the current passing through the winding 22 is not sufficient to effect retraction of the plunger and consequently after the contacting element D has been locked in circuit closing position, it will not be released until a current of suitable strength has been caused to pass through the windings to lift the plunger.

Having defined the structural features of this invention, its operation is as follows:

Operation Assuming the several components of this invention to be in their normal or open-circuit positions as shown in Fig. 1, when the mine containing this device is struck with sufiicient force to tilt the casing A approximately 45 from the perpendicular, spherical contact D, rolling outwardly over its inclined race l2 under the action of gravity, becomes wedged between surface [2, plate l5, and the tapered surface of plunger 16, thus closing the circuit between electrodes B and C, as clearly shown in the drawing.

As spherical contact D leaves its normal position beneath plunger l the latter drops by gravity, thus preventing return of the spherical contact and securing it in its closed-circuit position. When a mine in a mine-field, previously rendered harmless, has been struck by a vessel passing through the field, the impact actuates the spherical contact of the mine to closed-circuit position. To restore the spherical contact to open-circuit position, the requisite circuit is closed to energize the electro-responsivc device E, whereupon head it of plunger I6 is retracted within sleeve 23. The retractile movement of head it" withdraws the plunger $6 from the path of spherical ontact D and permits the latter to return to its normal position on electrode B to reestablish open-circuit conditions.

The mass of contact plate i5, the resiliency of spring it, the mass of spherical contact D, the weight and slight lateral play of plunger 56 and coeincient of friction between the surfaces, all unitedly function to provide the requisite yielding resistance to overcome the impact of the contacting elements. This resistance not only prevents damage to said elements but likewise the instantaneous rebound caused by their sudden contact, which obviously, if permitted, would be highly detrimental to the proper function of the apparatus.

Although in the foregoing I have described certain elements as best adapted to perform the functions allotted to them, nevertheless, it is to be understood that various changes, especially with respect to the character of apparatus with which this invention is to be used may be resorted to within the scope of the appended claims, without departing from or sacrificing any of the principles of this invention.

Having described my invention, what I claim as new and wish to secure by Letter Patent is:

1. A device of the character described comprising a lower electrode normally disposed in a plane perpendicular to the horizontal and including a frusto-conical shaped metallic contact surface terminating at its lower end in an insulating zone, an upper electrode vertically spaced with respect to the lower electrode and comprising a spring pressed contact plate supported for movement along and about its vertical axis, a weighted plunger movable through the plate, a spherical member of conductive material adapted to establish an electrical path between the electrodes and normally held at rest on the insulated zone by the plunger which it normally supports in an elevated position, said spherical member when the lower electrode has been tilted to a predetermined angle relative to the perpendicular being adapted by its movement to displace the plunger and move said plate against the action of its spring, whereby the plunger descending to a position intercepting the return movement of the spherical member, locks the latter in wedged relation with respect to the contact surfaces of the upper and lower electrodes, and an electroresponsive device coacting with the plunger to effect its withdrawal from the path of the spherical member to permit the return of said member to its normal position under the action of the spring pressed contact plate.

2. A device of the character described comprising a lower electrode normally disposed in a plane perpendicular to the horizontal and including a fr-usto-conical shaped metallic contact surface terminating at its lower end in an insulating Zone, an upper electrode normally spaced with respect to the lower electrode, and comprising a spring pressed contact plate supported for movement along and about its vertical axis, a weighted plunger movable through the plate, a spherical member of conductive material adapted to establish an electrical path between the electrodes and normally held on the insulated zone by the plunger, which it normally supports in an elevated position, said spherical member when the electrode has been tilted approximately 45 from the perpendicular, being adapted to displace the plunger and move said plate against the action of its spring whereby the plunger descending to a position intercepting the return movement of the spherical member locks the latter in wedged relation with respect to the contact surfaces of the upper and lower electrodes.

3. A device of the character described comprising a pair of vertically spaced electrodes adapted to be normally supported in a plane perpendicular to the horizontal, one of the electrodes including a yieldably supported metallic contact plate, the other an inclined metallic surface centrally formed with an insulating zone, a Weighted plunger operable through the plate, a spherical member of conductive material disposed between the electrodes and normally held at rest on the insulated zone by the plunger which it normally supports in an elevated position, said spherical member when said electrodes have been tilted to a predetermined angle with respect to the perpendicular being adapted by its movement to displace the plunger and said contact plate whereby the plunger descending to a position intercepting the return movement of the spherical member locks the latter in wedged relation with respect to the contact surfaces of said electrodes, and means for effecting restoration of the spherical member and plunger to their normal positions.

4. A device of the character described comprising, in combination, a pair of vertically spaced electrodes, normally disposed in a plane perpendicular to the horizontal, a spherical member of conducting material having open and closed circuit positions and movable from one position to the other, means normally seating the spherical member in open circuit position between the electrodes, means associated with the respective electrodes for disposing and securing the spherical member in closed circuit position when the electrodes have been tilted from the perpendicular, said last-mentioned means including a retractible plunger normally supported by said spherical member but displaceable by movement of said spherical member from open to closed circuit position, said plunger after displacement descending to a position preventing return of said spherical member to open circuit position, and electromagnetic means coacting with said plunger for efiecting its retraction to permit return of the spherical member to open circuit position.

HAROLD P. DETWILER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Nelson Mar. 20, 1928 Okey Sept. 18, 1917 Golombowski Jan. 17, 1928 Number Number 

